For example, WO 00/27721 discloses a plastic bag including a panel portion and a fastener portion. The panel portion is formed of first and second webs of panel material superposed with each other. The fastener portion is formed of first and second bodies of fastener material to extend along the top edge of the plastic bag. The first web of panel material and the first body of fastener material are joined to each other while the second web of panel material and the second body of fastener material are joined to each other within the plastic bag. The first and second bodies of fastener material are meshing engaged with each other so that the plastic bag can be closed by the first and second bodies of fastener material. The fastener portion comprises a hook and loop fastener portion. The plastic bag would be used for various purposes to be high in utility, regardless of a problem of airtightness of hook and loop fastener portion.
On the other hand, U.S. Pat. No. 7,331,917 discloses a machine for successively making plastic bags in which first and second webs of panel material are superposed with each other and fed longitudinally thereof. The machine includes longitudinal and cross seal devices by which the first and second webs of panel material are heat sealed with each other longitudinally and widthwise thereof. The first and second webs of panel material are then cross cut widthwise thereof by a cutter. The machine is efficient and effective. It can successively make plastic bags at high speed, resulting in high performance.
It is therefore required to successively make plastic bags in the form of the machine of U.S. Pat. No. 7,331,917, each of the plastic bags including a fastener portion so that the plastic bag can be closed by first and second bodies of fastener material as in the case of the plastic bag of WO 00/27721. In order to fulfill the requirement, the first and second bodies of fastener material have to extend in a direction of length of webs of panel material between the first and second webs of panel material. In addition, it is preferable that in the first place, the first and second bodies of fastener material advance in a direction of width of webs of panel material which is an advancing direction, to be inserted between the first and second webs of panel material. The advancing direction should then be changed into the direction of length of webs of panel material between the first and second webs of panel material.
It is therefore an object of the invention to provide a fastener material advancing direction changing apparatus in which first and second bodies of fastener material advance in a first direction which is an advancing direction, the advancing direction being then changed into a second direction.